On the basis of three pairs of isogenic lines of the garden pea and a pair of lines of Lathyrus sativus, differed only by alleles of histone H1 genes a phenotypic effect of substitution of allelic molecular variants of certain H1 subtypes has been studied. Certain statistically significant differences in a few quantitative characters were observed, including the seed productivity. A number of induced pea morphological mutants were mapped: Twt, ug, blb, vam - in the linkage group 1, a-2, fix, Enod12A - in the linkage group 3, Sgm - in the linkage group 5. Naturally occurring biochemical polymorphism allowed to map His7 gene and pp3 (a pollen protein) - in the linkage group 1 and SCA (a cotyledon protein) - in the linkage group 5. A more precise location on the genetic map of the known loci Aat-p, tac, coch, curl, lum-3, cri was carried out. Numerous segregation tests conducted on the lines with normal Karyotype and carrying translocation evidenced equivocally that the map segment d - Idh does not belong to the linkage group 1, some evidence being obtained that it should be attributed to linkage group 6. On the basis of the data obtained the following new versions of linkage maps based on morphological and biochemical markers have been suggested:
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Linkage group 1 |
aat-p His26 a lf Twt vam His7 blb |------------------|-|-----|-|-|------------|--------------| 0 37 43 51 52 53 71 89
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Linkage group 3 |
M fix a-2 tac st b Enod12A sym7 |-------|--|-----|---------|--------------|-------|--------| 0 19 21 32 55 90 107 127
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Linkage group 5 |
coch curl bt Sgm det r tl His1|Sca| lum3 gp U cri cp Fs |--|-------|---|--|----|-|-|-|------|---|--|-|---|---------| 0 6 29 34 36 46 48 50 51 73 83 89 90 105 135
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A number of chromosome rearrangements (translocations, a deletion covering the locus tl and a probable inversion in the region a - lf) were induced and/or characterized. They served for constructing genetic systems with artificially maintained heterozygosity useful for searching and mapping of new mutations in particular genome region and may be a basis for creating balance systems in pea. Development of a stable trisomic pea lines is in progress.